﻿function isNumberKey(sender, evt) {
    var txt = sender.value;
    var dotcontainer = txt.split('.');
    var charCode = (evt.which) ? evt.which : event.keyCode;
    if (!(dotcontainer.length == 1 && charCode == 46) && charCode > 31 && (charCode < 48 || charCode > 57))
        return false;
    return true;
}